plotter simulation with NI4882

[etech_stud]

Hello,

 i am trying to simulate a plotter with an c++ application, using the NationalInstruments::NI4882 namespace (Board Class). I want to read the hpgl data and save it to a text file.

With the most devices it works fine, but some HP analyzer are sending the "OS" command before sending the hpgl data.

Now my application has to answer on this command, but i am not sure what i have to answer?!

The next problem is, i pass the bus control to the device, after that the device is sending the "OS" comman. But i cannot answer to this command, because the device is the cic (controller in charge) at this moment. How can i get CIC to answer to the "OS" command?

[Lambsauce · Accepted solution]

Hello,

To make sure we understand, your application involves passing control (CIC) to one of the other nodes in the GPIB network.  At that point, the new CIC sends an OS command to your computer.

I'm assuming that if you use a simple device level ibwrt that you will get an ECIC error since the NI GPIB controller is no longer the CIC.  The way around this is to use a board level ibwrt.  The new CIC is handling the addressing, so using ibfind "GPIB0" and then ibwrt to send a response (whatever the CIC expectes) should be enough to get the response to the new CIC. 

Let us know if using board level calls worked.  If not, please let us know if you are getting any errors and let us know the behavior of the new CIC.

-Lamb